1. Field of the Invention
The present invention relates to an injection molding apparatus and, more particularly, to an apparatus and method for sensing an actuator position.
2. Related Art
The injection molding environment is subject to high heat, temperature cycling, and vapors and residues which may be corrosive or form gummy deposits. Moving parts required to function in such an environment, besides having to be designed against such conditions, are sometimes provided with transducers to detect position, speed, and other attributes for effective control of an injection molding apparatus. For example, an actuator may be provided with mechanical limit switches that are triggered by a moving part of the actuator to indicate a position of part of the injection molding apparatus.
However, switches such as the above can wear out or fail, which is usually compounded by a hostile molding environment, can be unduly influenced by temperature, and are not readily adaptable to monitoring complex parts or parts with unusual modes of operation.